There are two primary multi-step manufacturing processes for producing flexible reinforced rubber parts. One process involves hot curing at very high temperatures, with application of positive pressure during the curing process. Typically, the rubber and reinforcing material are combined on or in a tool or mandrel and then cured in an oven. Manufacturing tooling for this process is expensive and time consuming, making large quantities necessary for cost effectiveness. Flexible reinforced rubber parts requiring high temperature and positive pressure processes include tires and flexible ducting for gas and liquids.
The other main prior art method for fabricating flexible rubber reinforced parts uses a room temperature cure with no added pressure. The rubber and reinforcing material are applied to a tool and then cured at room temperature for a specific time period. As with the high temperature/positive pressure method, manufacturing tooling is costly and time intensive. Flexible reinforced rubber parts fabricated using room temperature curing include flexible ducting for gases and liquids.
The main disadvantage of the room temperature method is the tooling and time effort required to produce the part. Three separate tools are required to fabricate a single part. Moreover, additional parts require a wash-away tool for each part fabricated. The entire process is labor and time intensive. The lengthy in-process time also contributes to the possibility of human error.
Another disadvantage of the prior art methods is the cost and schedule impacts incurred when incorporating design changes after the tool has been fabricated. Often, such changes may require that the entire tooling process be repeated.
Stereolithography is a three-dimensional process that produces copies of solid or surface models in plastic using a computer-aided design system. Although stereolithography has been used in various applications, it has not been applied in the process of fabricating reinforced rubber parts.